Since 2008, falls have been designated as 1 of 11 preventable hospital-acquired conditions (HACs) for which the Centers for Medicare and Medicaid Services does not reimburse hospitals if the condition was not present on admission. Despite this financial incentive and support from the federally-funded Partnerships for Patients, AHRQ's most recent annual update on HACs reported limited progress in decreasing injury from falls. Two factors may explain this lack of progress. First, fall rates continue to be designated a nursing-sensitive indicators of quality that link unit-based nursing structures directly to the outcome of fall rates without identifying the intervening processes needed to keep patients safe from falls. Second, healthcare is a complex sociotechnical system-human beings work in social structures within complex technical environments to achieve system goals such as fall risk reduction that require coordinated action within and between teams. A multiteam system (MTS) is made up of two or more interdependent component teams that interact to achieve an overarching organizational goal. A healthcare MTS consists of at least three components: coordinating teams that coordinate processes across teams, core teams that provide direct patient care, and contingency teams composed of members from various component teams who come together to learn from events in real time and provide feedback to other component teams. The long-range goal of this project is to simultaneously advance the science of multiteam systems and patient safety by explaining how and why coordination within multiteam systems makes healthcare safer. The objective of this research project is to analyze existing data collected from 17 hospitals that implemented a multiteam system approach to decrease fall risk among priority rural older adult populations. This long-range goal and objective are consistent with the mission of the Agency for Healthcare Research and Quality, which is to produce evidence to make healthcare safer, higher quality...and to ensure that evidence is understood and used. The three aims of this project are to: (1) determine the structure of effective fall risk reduction coordinating teams, (2) determine the relationship between coordinating team processes and fall rates, and 3) determine the relationship between participation in contingency teams and perceptions of coordinating team effectiveness. This project is innovative because our longitudinal, quantitative and qualitative data overcomes barriers to MTS research, which include limited access to multiteam systems in real world healthcare settings and the complexity of collecting and analyzing multilevel, longitudinal data. This project will make a significant contribution to public health by demonstrating that adoption of a MTS structure and coordination processes in the context of fall risk reduction has the potential to accelerate national progress in reducing injury from falls.